docs: def _get_plugin_module_paths(self, plugin_dir):
          ''' Return a list of every module in `plugin_dir`. '''
          filepaths = [
              fp for fp in glob.glob('{}/**/*.py'.format(plugin_dir), recursive=True)
              if not fp.endswith('__init__.py')
          ]
          rel_paths = [re.sub(plugin_dir.rstrip('/') + '/', '', fp) for fp in filepaths]
          module_paths = [rp.replace('/', '.').replace('.py', '') for rp in rel_paths]
  
          return module_paths